Internet Engineering Task Force (IETF) S. Das
Request for Comments: 6153 Telcordia Technologies
Category: Standards Track G. Bajko
ISSN: 2070-1721 Nokia
February 2011
Internet Engineering Task Force (IETF) S. Das
Request for Comments: 6153 Telcordia Technologies
Category: Standards Track G. Bajko
ISSN: 2070-1721 Nokia
February 2011
DHCPv4 and DHCPv6 Options for Access Network Discovery and Selection Function (ANDSF) Discovery
用于接入网发现和选择功能（ANDSF）发现的DHCPv4和DHCPv6选项
Abstract
摘要
This document defines new Dynamic Host Configuration Protocol (DHCPv4 and DHCPv6) options to enable a mobile node to discover Access Network Discovery and Selection Function (ANDSF) entities in an IP network. ANDSF is being developed in the Third Generation Partnership Project (3GPP) and provides inter-system mobility policies and access-network-specific information to the mobile nodes (MNs).
本文档定义了新的动态主机配置协议（DHCPv4和DHCPv6）选项，以使移动节点能够发现IP网络中的接入网络发现和选择功能（ANDSF）实体。ANDSF正在第三代合作伙伴计划（3GPP）中开发，并向移动节点（mn）提供系统间移动性策略和接入网络特定信息。
Status of This Memo
关于下段备忘
This is an Internet Standards Track document.
这是一份互联网标准跟踪文件。
This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 5741.
本文件是互联网工程任务组（IETF）的产品。它代表了IETF社区的共识。它已经接受了公众审查，并已被互联网工程指导小组（IESG）批准出版。有关互联网标准的更多信息，请参见RFC 5741第2节。
Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc6153.
有关本文件当前状态、任何勘误表以及如何提供反馈的信息，请访问http://www.rfc-editor.org/info/rfc6153.
Copyright Notice
版权公告
Copyright (c) 2011 IETF Trust and the persons identified as the document authors. All rights reserved.
版权所有（c）2011 IETF信托基金和确定为文件作者的人员。版权所有。
This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License.
本文件受BCP 78和IETF信托有关IETF文件的法律规定的约束(http://trustee.ietf.org/license-info)自本文件出版之日起生效。请仔细阅读这些文件，因为它们描述了您对本文件的权利和限制。从本文件中提取的代码组件必须包括信托法律条款第4.e节中所述的简化BSD许可证文本，并提供简化BSD许可证中所述的无担保。
Table of Contents
目录
1. Introduction ....................................................2
1.1. Conventions Used in This Document ..........................3
1.2. Terminology and Abbreviations Used in This Document ........3
2. ANDSF IPv4 Address Option for DHCPv4 ............................3
3. ANDSF IPv6 Address Option for DHCPv6 ............................4
4. Option Usage ....................................................4
4.1. Usage of ANDSF Options for DHCPv4 ..........................4
4.1.1. Mobile Node Behavior ................................4
4.2. Usage of ANDSF Options for DHCPv6 ..........................5
4.2.1. Mobile Node Behavior ................................5
5. Security Considerations .........................................5
6. IANA Considerations .............................................5
7. Acknowledgments .................................................6
8. References ......................................................6
8.1. Normative References .......................................6
8.2. Informative References .....................................6
1. Introduction ....................................................2
1.1. Conventions Used in This Document ..........................3
1.2. Terminology and Abbreviations Used in This Document ........3
2. ANDSF IPv4 Address Option for DHCPv4 ............................3
3. ANDSF IPv6 Address Option for DHCPv6 ............................4
4. Option Usage ....................................................4
4.1. Usage of ANDSF Options for DHCPv4 ..........................4
4.1.1. Mobile Node Behavior ................................4
4.2. Usage of ANDSF Options for DHCPv6 ..........................5
4.2.1. Mobile Node Behavior ................................5
5. Security Considerations .........................................5
6. IANA Considerations .............................................5
7. Acknowledgments .................................................6
8. References ......................................................6
8.1. Normative References .......................................6
8.2. Informative References .....................................6
Access Network Discovery and Selection Function (ANDSF) is being defined in 3GPP [3GPPTS23.402] to provide necessary network discovery and selection assistance data to the mobile nodes for multi-access network scenarios where 3GPP access-network level solutions are not sufficient for the mobile nodes to perform network discovery and selection of non-3GPP networks.
接入网络发现和选择功能（ANDSF）在3GPP[3GPPTS23.402]中定义在3GPP接入网络级解决方案不足以让移动节点执行非3GPP网络的网络发现和选择的多接入网络场景中，向移动节点提供必要的网络发现和选择辅助数据。
The information provided by ANDSF contains inter-system mobility policies and access-network-specific data to assist the mobile node with performing the inter-system handover. This set of information can either be provisioned in the mobile node by the home operator or provided to the mobile node (MN) dynamically by the ANDSF over the S14 reference point as defined in [3GPPTS23.402] and [3GPPTS24.302].
ANDSF提供的信息包含系统间移动策略和接入网络特定数据，以帮助移动节点执行系统间切换。该组信息可以由归属运营商在移动节点中提供，或者由ANDSF在[3GPPTS23.402]和[3GPPTS24.302]中定义的S14参考点上动态地提供给移动节点（MN）。
In 3GPP, the ANDSF is located either in the subscriber's home operator or visited network and needs to be known to the MN or discovered by the MN. According to [3GPPTS23.402] and [3GPPTS24.302], the ANDSF is discovered through interaction with the Domain Name Service function or the DHCP server function.
在3GPP中，ANDSF位于用户的家庭运营商或访问网络中，并且需要被MN知道或被MN发现。根据[3GPPTS23.402]和[3GPPTS24.302]，通过与域名服务功能或DHCP服务器功能的交互来发现ANDSF。
This document defines new DHCPv4 and DHCPv6 options called the ANDSF IP Address Options, which allow the MN to locate an ANDSF server.
本文档定义了新的DHCPv4和DHCPv6选项，称为ANDSF IP地址选项，允许MN定位ANDSF服务器。
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119].
本文件中的关键词“必须”、“不得”、“必需”、“应”、“不应”、“应”、“不应”、“建议”、“可”和“可选”应按照[RFC2119]中所述进行解释。
ANDSF (Access Network Discovery and Selection Function): An entity that provides network discovery and selection assistance data to the user entity (UE) as per operator policy [3GPPTS23.402].
ANDSF（接入网发现和选择功能）：根据运营商策略[3GPPTS23.402]向用户实体（UE）提供网络发现和选择辅助数据的实体。
Access Network: A network that is accessed by the UE.
接入网络：由UE接入的网络。
3GPP Network: A radio access network specified by Third Generation Partnership Project
3GPP网络：第三代合作伙伴计划指定的无线接入网络
Non-3GPP Network: A radio access network specified outside 3GPP by other projects or standards organizations
非3GPP网络：由其他项目或标准组织在3GPP之外指定的无线接入网络
This section describes the ANDSF IPv4 Address Option for DHCPv4. The option layout is depicted below:
本节介绍DHCPv4的ANDSF IPv4地址选项。选项布局如下所示：
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Option Code | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IP Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
. .
+---------------------------------------------------------------+
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Option Code | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IP Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
. .
+---------------------------------------------------------------+
Option Code OPTION-IPv4_Address-ANDSF (142)
选项代码选项-IPv4_地址-ANDSF（142）
Length Length (in bytes) of the option excluding the 'Option Code' and the 'Length' fields; 'Length' field is set to 4N, where N is the number of IPv4 addresses carried in the option
选项的长度（字节），不包括“选项代码”和“长度”字段；'“长度”字段设置为4N，其中N是选项中携带的IPv4地址数
IP Address IPv4 address(es) of ANDSF server(s)
ANDSF服务器的IP地址IPv4地址
ANDSF servers MUST be listed in order of preference, and the client SHOULD process them in decreasing order of preference.
ANDSF服务器必须按首选项的顺序列出，客户端应按首选项的降序处理它们。
This section describes the ANDSF IPv6 Address Option for DHCPv6. All values in the option are represented in network byte order. The option layout is depicted below:
本节介绍DHCPv6的ANDSF IPv6地址选项。选项中的所有值均以网络字节顺序表示。选项布局如下所示：
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Option Code | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IP Address |
. .
+---------------------------------------------------------------+
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Option Code | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IP Address |
. .
+---------------------------------------------------------------+
Option Code OPTION-IPv6_Address-ANDSF (143)
选项代码选项-IPv6\U地址-ANDSF（143）
Length Length (in bytes) of the option excluding the 'Option Code' and the 'Length' fields; 'Length' field is set to 16N, where N is the number of IPv6 addresses carried in the option
选项的长度（字节），不包括“选项代码”和“长度”字段；'“长度”字段设置为16N，其中N是选项中携带的IPv6地址数
IP Address IPv6 address(es) of ANDSF server(s)
IP地址ANDSF服务器的IPv6地址
ANDSF servers MUST be listed in order of preference, and the client SHOULD process them in decreasing order of preference.
ANDSF服务器必须按首选项的顺序列出，客户端应按首选项的降序处理它们。
The requesting and sending of the proposed DHCPv4 options follow the rules for DHCP options in [RFC2131].
建议的DHCPv4选项的请求和发送遵循[RFC2131]中DHCP选项的规则。
The mobile node MAY request the IP address of an ANDSF server either during initial association with a network or when the policy and access network information is required from ANDSF. It MAY also request the IP address of an ANDSF server when the network information is outdated or the mobile node does not have any ANDSF information.
移动节点可以在与网络的初始关联期间或当需要来自ANDSF的策略和访问网络信息时请求ANDSF服务器的IP地址。当网络信息过时或移动节点没有任何ANDSF信息时，它还可以请求ANDSF服务器的IP地址。
In order to request an address of a ANDSF server, the mobile node (DHCP client) MUST include an ANDSF IPv4 Address Option in the Parameter Request List (PRL) in the respective DHCP messages as
为了请求ANDSF服务器的地址，移动节点（DHCP客户端）必须在相应DHCP消息的参数请求列表（PRL）中包括ANDSF IPv4地址选项，如下所示：
defined in [RFC2131] and [RFC2132]. The DHCP client MAY initiate a new DHCP exchange or piggyback on other DHCP message exchanges. DHCP client-handling PRL options are specified in [RFC2131], Section 4.4.
在[RFC2131]和[RFC2132]中定义。DHCP客户端可以启动一个新的DHCP交换，或者在其他DHCP消息交换上进行搭载。[RFC2131]第4.4节规定了DHCP客户端处理PRL选项。
The requesting and sending of the proposed DHCPv6 options follow the rules for DHCP options in [RFC3315].
建议的DHCPv6选项的请求和发送遵循[RFC3315]中DHCP选项的规则。
The mobile node MAY request the IP address of an ANDSF server according to the scenarios described in Section 4.1.1.
移动节点可根据第4.1.1节中描述的场景请求ANDSF服务器的IP地址。
In order to discover the address of an ANDSF server, the mobile node (DHCP client) MUST include an ANDSF IPv6 Address Option in the Option Request Option (ORO) in the respective DHCP messages as defined in [RFC3315]. The DHCP client MAY initiate a new DHCP exchange or piggyback on other DHCP message exchanges. DHCP client-handling ORO options are specified in [RFC3315], Sections 17.1 and 18.1.
为了发现ANDSF服务器的地址，移动节点（DHCP客户端）必须在[RFC3315]中定义的相应DHCP消息的选项请求选项（ORO）中包含ANDSF IPv6地址选项。DHCP客户端可以启动一个新的DHCP交换，或者在其他DHCP消息交换上进行搭载。[RFC3315]第17.1和18.1节规定了DHCP客户端处理ORO选项。
If an adversary manages to modify the response from a DHCP server or insert its own response, an MN could be led to contact a rogue ANDSF server. A modified response could also be used to mount an amplification attack.
如果对手设法修改DHCP服务器的响应或插入自己的响应，MN可能会被引导与恶意ANDSF服务器联系。修改后的响应也可用于发起放大攻击。
The DHCP authentication option described in [RFC3118] and [RFC3315] MAY be used to mitigate the above attacks. In deployments where DHCP authentication is not available, 3GPP-specific lower-layer security services can be used to protect DHCP messages [3GPPTS33.402]. The 3GPP ANDSF framework also provides additional mechanisms that can be used to mitigate the above attacks and to protect message exchanges between an ANDSF client and server at the higher layer [3GPPTS33.402].
[RFC3118]和[RFC3315]中描述的DHCP身份验证选项可用于缓解上述攻击。在DHCP身份验证不可用的部署中，可以使用3GPP特定的低层安全服务来保护DHCP消息[3GPPTS33.402]。3GPP和SF框架还提供了额外的机制，可用于缓解上述攻击，并在更高层保护和SF客户端与服务器之间的消息交换[3GPPTS33.402]。
This document defines two new DHCP options as described in Sections 2 and 3:
本文件定义了两个新的DHCP选项，如第2节和第3节所述：
ANDSF IPv4 Address Option for DHCPv4 (OPTION-IPv4_Address-ANDSF) 142
DHCPv4的ANDSF IPv4地址选项（选项-IPv4_地址-ANDSF）142
ANDSF IPv6 Address Option for DHCPv6 (OPTION-IPv6_Address-ANDSF) 143
DHCPv6的ANDSF IPv6地址选项（选项-IPv6_地址-ANDSF）143
The authors would like to acknowledge the following individuals for their valuable comments: Patrick Stuper, Vijay Devarapalli, Jouni Korhonen, Jari Arkko, Ted Lemon, and Ralph Droms.
作者要感谢以下个人的宝贵意见：帕特里克·斯图珀、维杰·德瓦拉帕利、朱尼·科霍宁、贾里·阿尔科、特德·莱蒙和拉尔夫·德罗姆斯。
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2119]Bradner，S.，“RFC中用于表示需求水平的关键词”，BCP 14，RFC 2119，1997年3月。
[RFC2131] Droms, R., "Dynamic Host Configuration Protocol", RFC 2131, March 1997.
[RFC2131]Droms，R.，“动态主机配置协议”，RFC21311997年3月。
[RFC2132] Alexander, S. and R. Droms, "DHCP Options and BOOTP Vendor Extensions", RFC 2132, March 1997.
[RFC2132]Alexander，S.和R.Droms，“DHCP选项和BOOTP供应商扩展”，RFC 21321997年3月。
[RFC3315] Droms, R., Ed., Bound, J., Volz, B., Lemon, T., Perkins, C., and M. Carney, "Dynamic Host Configuration Protocol for IPv6 (DHCPv6)", RFC 3315, July 2003.
[RFC3315]Droms，R.，Ed.，Bound，J.，Volz，B.，Lemon，T.，Perkins，C.，和M.Carney，“IPv6的动态主机配置协议（DHCPv6）”，RFC3315，2003年7月。
[RFC3118] Droms, R., Ed., and W. Arbaugh, Ed., "Authentication for DHCP Messages", RFC 3118, June 2001.
[RFC3118]Droms，R.，Ed.，和W.Arbaugh，Ed.，“DHCP消息的身份验证”，RFC31182001年6月。
[3GPPTS23.402] 3GPP TS 23.402, v8.8.0 (2009-12): Architecture enhancements for non-3GPP accesses, http://www.3gpp.org/ftp/Specs/html-info/23402.htm.
[3GPPTS23.402]3GPP TS 23.402，v8.8.0（2009-12）：非3GPP接入的架构增强，http://www.3gpp.org/ftp/Specs/html-info/23402.htm.
[3GPPTS24.302] 3GPP TS 24.302, v8.4.1 (2009-12): Access to the 3GPP Evolved Packet Core (EPC) via non-3GPP access networks; Stage 3, http://www.3gpp.org/ftp/Specs/html-info/24302.htm.
[3GPPTS24.302]3GPP TS 24.302，v8.4.1（2009-12）：通过非3GPP接入网络访问3GPP演进包核心（EPC）；第三阶段，http://www.3gpp.org/ftp/Specs/html-info/24302.htm.
[3GPPTS33.402] 3GPP TS 33.402, v8.6.0 (2009-12): 3GPP System Architecture Evolution (SAE); Security aspects of non-3GPP accesses, http://www.3gpp.org/ftp/Specs/html-info/33402.htm.
[3GPPTS33.402]3GPP TS 33.402，v8.6.0（2009-12）：3GPP系统架构演进（SAE）；非3GPP接入的安全方面，http://www.3gpp.org/ftp/Specs/html-info/33402.htm.
Authors' Addresses
作者地址
Subir Das Telcordia Technologies Inc. EMail: subir@research.telcordia.com
Subir Das Telcordia Technologies Inc.电子邮件：subir@research.telcordia.com
Gabor Bajko Nokia EMail: gabor@bajko.nokia.com
Gabor Bajko诺基亚电子邮件：gabor@bajko.nokia.com